Athlete mentor Rachael Mackenzie is preparing to take on her toughest challenge yet for a new BBC documentary.

Mrs Mackenzie, a former world champion Thai boxer, will climb Mount Everest with troubled youths for a programme called Extreme Classroom Project.

She said: “The aim of the Extreme Classroom Project is to show that there are different ways to educate people than just in a classroom.

“The programme is called The World’s Highest Classroom, because the expedition itself is a theoretical classroom that the children are learning in.

“We take children with educational behavioural difficulties on an expedition and they really develop the life skills they wouldn’t have otherwise.”

The mum of twins, who lives in Harrogate, has already ventured to the Arctic for BBC programmes The World’s Coldest Classroom and The World’s Hottest Classroom, where she hiked through the African Rift Valley in Tanzania.

She said: “The cold of the Arctic was a real challenge and I ended up dragging kit for some of the children who couldn’t manage.

“But the altitude of Everest will be really tough; no matter how fit you are you can’t train for altitude.”

The Extreme Classrooms project is led by Trystan Williams, principal at The Springfields Academy in Wiltshire. It is open to children with special educational needs across the UK, although applicants are required to undergo a series of rigorous challenges to prove they can meet the physical and mental demands that lie in wait.

Mrs Mackenzie said: “Trystan wanted athletes as mentors as they are both mentally and physically capable of these challenges.

“The changes in the children are huge. They are used to failing and often don’t like to rely on people but in situations like those they have to. Within days they have opened up to us, which is just amazing.”